[Extenisons Bindings] Don't throw unchecked errors; add console errors

extensions/renderer/api_last_error.h

Index: extensions/renderer/api_last_error.h
diff --git a/extensions/renderer/api_last_error.h b/extensions/renderer/api_last_error.h
index 95126fe62fc5e148a695c0c32fb811985708cb85..686adcc9ca789dcd8eedf2b612292ec16e0b160e 100644
--- a/extensions/renderer/api_last_error.h
+++ b/extensions/renderer/api_last_error.h
@@ -21,8 +21,12 @@ class APILastError {
   // given context.
   using GetParent =
       base::Callback<v8::Local<v8::Object>(v8::Local<v8::Context>)>;
+  // Adds an error message to the context's console.
+  using AddConsoleError =
+      base::Callback<void(v8::Local<v8::Context>, const std::string& error)>;
 
-  explicit APILastError(const GetParent& get_parent);
+  APILastError(const GetParent& get_parent,
+               const AddConsoleError& add_console_error);
   APILastError(APILastError&& other);
   ~APILastError();
 
@@ -39,6 +43,8 @@ class APILastError {
  private:
   GetParent get_parent_;
 
+  AddConsoleError add_console_error_;
+
   DISALLOW_COPY_AND_ASSIGN(APILastError);
 };